[commit: ghc] wip/T8584: Add support for pattern synonym type signatures. Syntax is of the form (34acc90)

[Dr. ERDI Gergo]

On Wed, 19 Nov 2014, Simon Peyton Jones wrote:

> I've lost track.  Is this ready to commit?

I have just today finished it completely, implementation-wise. It 
validates and contains Haddock updates as well, to use the same syntax as 
the frontend.

I will be updating the documentation tomorrow and then merging it.

I'll send an email to ghc-devs about it, to make sure it makes it in 
before the feature freeze.

Bye,
 	Gergo